The present invention relates to in-floor towline conveyors and more particularly to towline conveyors including a powered main line having a chain adapted to pull a truck or cart along the floor and one or more non-powered spur lines.
In-floor towline conveyors include a track or channel defining a slot and within which a powered chain rides. The powered chain includes a plurality of longitudinally spaced pusher dogs adapted to engage the towpin of the cart or truck in order to mechanically guide and pull the truck along the floor on a predetermined conveyor layout. Such systems will typically include one or more branch or spur lines at which carts or trucks may be accumulated for storage, loading or unloading purposes. If the spur is non-powered, the carts must be manually pushed back to the main line slot at which their respective towpins will re-engage a pusher dog of the main line conveyor chain.
Examples of in-floor towline conveyor systems may be found in U.S. Pat. No. 3,048,126 to Salapatas, entitled CONVEYOR INSTALLATION FOR WHEELED CARTS and issued on Aug. 7, 1962; U.S. Pat. No. 3,027,850 to Burrows, entitled CONVEYOR SYSTEMS and issued Apr. 30, 1962; U.S. Pat. No. 3,127,849 to Klamp entitled SUB-FLOORING CONVEYOR CONTROL SYSTEM and issued Apr. 7, 1964.
In the aforementioned Burrows patent, a system is disclosed for transferring a cart or truck from one powered line to another powered line of an in-floor towline conveyor. The transfer system or mechanism includes a hydraulically actuated ram. The ram engages the towpin of the cart to be transferred and pushes that cart between the powered lines. A ramp is provided at the entry point to raise the towpin of a cart to a position above the towline chain where it may drop into an empty pusher dog.